Electron diffraction and high resolution microscopy have been performed on Mg1-xAlxB2 with x≅0.5. This composition displays a superstructure with a repeat period of exactly 2c along the c-axis and about 10 nm in the a-b plane. The superstructure results in ring-shaped superreflections in the diffraction pattern. Irradiation by a strong electron beam results in a loss of the superstructure and a decrease of about 1% in the c lattice parameter. In situ heating and cooling on the other hand showed that the superstructure is stable from 100 to 700 K. Possible origins for the superstructure are proposed.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering
- Electron microscopy